How to maintain hard finger tips whilst travelling?

Hi all. I travel with work 2 to 3 nights a week and taking a guitar isn’t practicable, therefore my fingers don’t have time to harden. So each week it’s like starting again as I can only practice for a short while until my fingers get sore. Is there something I can take on the road with me that can help me harden my finger tips. Thanks in advance for any suggestions.

Well, there are travel guitars. But have you considered a ukulele?

No I hadn’t considered a ukulele, I will look into it thanks.